In recent years, the mouse has been widely used as a pointing device for a personal computer, etc. Additionally, because the cord which connects the mouse and the personal computer stands in the way while operating and carrying the mouse, the wireless mouse, in which the mouse is turned into a cordless device using wireless signals, has become popular. In general, the wireless mouse is connected to the personal computer, etc., through infrared rays and electromagnetic waves.
Although the mouse always has to be turned on to accept the input from a user, the abovementioned wireless mouse cannot receive an electric power supply; therefore, operation electric power in itself has to be secured using a battery, etc. In order to suppress electric power consumption, a technology that intentionally switches to a power save mode by pressing an operation interface for a predefined period of time has been published (see Japanese Published Unexamined Application No. 2005-267645).
Additionally, as for the movement of the mouse, the accuracy of a ball-type mouse easily decreases because of stains on the mounting surface; however, recently, the optical-type (optical) mouse, which is stain-resistant and which is easy to clean, has become mainstream. Such an optical mouse detects the displacement between the mouse and the mounting surface of the mouse by observing a reflected wave, such as an infrared ray, regardless of whether it is wireless or wired operation.
As described above, the wireless mouse consumes more electric power than a wired mouse due to transmission a communication signal (infrared rays and electromagnetic waves) to a personal computer. Additionally, the abovementioned optical mouse also consumes electric power further because it utilizes infrared rays. However, because the wireless mouse has no electric power supply paths such as the connecting wire that is provided in the wired mouse, generally, a power source such as a battery is installed inside; however, because it needs to be housed in the housing of the wireless mouse, there is no choice, but to use a small-sized battery comprising a small power storage capacity. As a result, the user is forced to perform burdensome operations such as replacement of a battery and is required to frequently purchase and replace the battery when, in particular, the optical wireless mouse is used. Therefore, further power saving of the optical wireless mouse has been expected.
However, in the wireless mouse according to the Japanese Published Unexamined Application No. 2005-267645, the user has to intentionally press the operation interface such as a switch in order to switch the wireless mouse to the power save mode. Therefore, even if the user possesses a mouse in which such technology is employed, the user will not make an effort to try to suppress the electric power consumption by going through complicated operations; thus, it is expected that such technology is not utilized effectively.